Re: [PATCH net-next v5 2/5] net: vxlan: add netlink option to bind vxlan sockets to local addresses

[Kuniyuki Iwashima]

On Wed, Aug 13, 2025 at 9:04 AM Ido Schimmel <idosch@xxxxxxxxxx> wrote:
>
> On Wed, Aug 13, 2025 at 05:46:44PM +0200, Richard Gobert wrote:
> > Kuniyuki Iwashima wrote:
> > > From: Richard Gobert <richardbgobert@xxxxxxxxx>
> > >> @@ -4044,15 +4045,37 @@ static int vxlan_nl2conf(struct nlattr *tb[], struct nlattr *data[],
> > >>            conf->vni = vni;
> > >>    }
> > >>
> > >> +  if (data[IFLA_VXLAN_LOCALBIND]) {
> > >> +          if (changelink) {
> > >> +                  NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_VXLAN_LOCALBIND], "Cannot rebind locally");
> > >> +                  return -EOPNOTSUPP;
> > >> +          }
> > >
> > > Are these two "if" necessary ?
> >
> > Creating a vxlan interface without localbind then adding localbind won't
> > result in the socket being rebound. I might implement this in the future,
> > but for simplicity, I didn't implement this yet.
>
> I think Kuniyuki meant that you can just call vxlan_nl2flag() without
> those two "if"s because the function is a NO-OP when the attribute is
> not present and it will also fail the changelink operation.

Yes, I don't know why other places were not converted as such
when vxlan_nl2flag() was introduced in 70fb0828800b.

>
> >
> > >
> > >
> > >> +
> > >> +          err = vxlan_nl2flag(conf, data, IFLA_VXLAN_LOCALBIND,
> > >> +                              VXLAN_F_LOCALBIND, changelink,
> > >> +                              false, extack);
> > >> +          if (err)
> > >> +                  return err;
> > >> +  }
> > >> +